Aaron Schock’s career unraveled in large measure because his staff tried to bully a reporter who wasn’t even investigating the congressman.

Now the underlying reason that the Illinois Republican announced his resignation on Tuesday had to do with arrogance over his free-spending habits and the urge to pursue a celebrity lifestyle. But Schock would have kept his House seat if his aides hadn’t gone ballistic over the “Downton Abbey” story.

I met Schock, who has a habit of being photographed shirtless, soon after he took office in 2009 when TMZ did a quick feature on his admirable abs. The freshman embraced the brief burst of celebrity, telling me that if voters are “learning about me on TMZ or some of these other blogs and YouTube videos, then they're recognizing my face and my name so when I'm out on CNN or some of the other networks talking about issues, they're maybe going to stop from clicking the channel and listen to what I have to say.”

I asked whether that sort of thing trivialized him. “I guess there's worse things they could be saying about you,” Schock told me.

Fast forward to last month, when a Style section reporter for the Washington Post, Ben Terris, dropped by the congressman’s office for a feature story and noticed the following: “Bright red walls. A gold-colored wall sconce with black candles. A Federal-style bull’s-eye mirror with an eagle perched on top.”

The interior decorator hired by Schock popped into the outer office and offered to give him a tour. The reporter took some pictures. The communications director called and demanded that Terris delete the pictures: “Who told you you could do that?”

Um, it’s a public office, paid for by the taxpayers?

“An office decorated in a unique way would hardly be surprising; it would just be another interesting fact about a congressman who has built a brand as not just another politician. So why was this a crisis?”

The attempt to strong-arm Terris into dropping what was dismissed as “some gossipy piece” probably brought the article a thousand times more attention when the Post said the office was done in the style of the hit PBS show.

Terris, for his part, is self-effacing, tweeting his thanks to an editor “who I called in a panic and asked if I really had to delete those photos. He told me no.”

And: “After my story about the office came out, it took a reporter smarter than I, @singernews to see the real problems.”

“Schock has spent tens of thousands of dollars from his taxpayer-funded accounts on renovations, leather furniture and even granite countertops, according to congressional expenditure reports.”

The 33-year-old congressman now had a giant target on his back. Already a minor celeb for his flashy ways — he was on the cover of Men’s Journal — his spending habits were pursued by several news organizations.

This simply wouldn’t have happened if not for the “Downton Abbey” tale; the investment of journalistic resources would not have been deemed worthwhile. But the media sensed an irresistible theme: Young man in a hurry spoiled by success, succumbs to Potomac fever.

“The AP's review identified at least one dozen flights worth more than $40,000 on donors' planes since mid-2011, tracking Schock's reliance on the aircraft partly through the congressman's penchant for uploading pictures and videos of himself to his Instagram account.”

Politico was aggressively pursuing Schock as well. Its story said his resignation came “less than 12 hours after POLITICO raised questions about tens of thousands of dollars in mileage reimbursements he received for his personal vehicle.

“Schock billed the federal government and his campaign for logging roughly 170,000 miles on his personal car from January 2010 through July 2014. But when he sold that Chevrolet Tahoe in July 2014, it had roughly 80,000 miles on the odometer, according to public records obtained by POLITICO under Illinois open records laws.”

With each passing story, it became harder to feel sorry for Schock. He said he is giving up his seat because “the constant questions over the last six weeks have proven a great distraction that has made it too difficult for me to serve the people of the 18th District.”

Richard Schock also told WBBM-TV that his son was “broken” and most of the allegations are “lies and innuendos”:

“What this is really about is that Aaron has been very successful. Aaron is a very hard worker. Aaron is very popular. Aaron is a little different. He wears stylish clothing, and yet he’s not gay … and he’s not married. … and he’s not running around with women. Everybody’s throwing up their arms. They can’t figure out Aaron. So he must be crooked. So attack him. Bring him down, because he doesn’t fit into our picture.”

I would say that Aaron Schock brought himself down — and it all started with the freakout over a reporter who walked into his redecorated office.